The present invention relates to a drilling device for cutting an elliptical opening in the jawbone in order to receive a tooth implant which has an implant holder that is implanted in the elliptical opening for supporting it. Once a substantially circular pilot opening is cut, it is advantageous to precisely cut a substantially elliptical opening so that it fits snugly with an elliptically cross-sectioned implant in order to guard against rotation of the implant as well as to have a broader surface for osteointegration.
Jaw implants in the jawbone are common and it has been found that one of the best shapes for anchoring the implant in the bone is by means of having a substantially elliptical or oval opening for receiving the implant. Accordingly, it is desirable to use a substantially elliptical or oval cross section in the implant; by being oval or substantially elliptical, with snug fit in the bone receptacle, the implant has the best chance of stimulating making a firm and stable connection with the cortical bone.
One of the disadvantages of using an oval cross section is that it is difficult to precisely cut the bone to form a precise oval opening that fits snugly with the implant.
It is therefore an object of this invention to provide an improved drill and an improved method of precisely drilling a substantially elliptical or oval hole in the cortical bone for anchoring tooth implants so that osteointegration will occur and the implant will have a firm seat and offer sufficiently great resistance to any forces that might ordinarily dislodge the implant.
Another object of the invention is to provide a very precise elliptical or oval opening to receive an implant having a cross section that is elliptical and has snug and intimate relation with the jawbone in order to prevent motion between the bone and the implant during the healing period.
A feature of the invention includes providing an adjustable drilling head whereby optimum positioning of the drilling head can be effected to more easily work in the patient's mouth.
One other feature of the invention includes having the cutters yieldingly operate by allowing them to retract when a force is encountered in contact with the bone, whereby trauma to the bone is reduced and the bone can be gradually cut with small shavings being removed therefrom.
The drilling device of this invention is comparable in size to a conventional surgical drilling head and is powered conventionally and has water flowing through to cool off the bone being cut as well as cleanse it. Also, the drilling instruments made in accordance with this invention are such that they can be associated with a number of conventional driving devices as will be shown and explained herein.